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Related papers: Ultrafast optical currents in gapped graphene

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We theoretically investigate the interaction of an ultrastrong femtosecond-long linearly polarized optical pulse with AB-stacked bilayer graphene. The pulse excite electrons from the valence into the conduction band, resulting in finite…

Mesoscale and Nanoscale Physics · Physics 2021-08-11 Pardeep Kumar , Thakshila M. Herath , Vadym Apalkov , Mark I. Stockman

We study the interaction of graphene with ultrashort few femtosecond long optical pulse. For such a short pulse, the electron dynamics is coherent and is described within the tight-binding model of graphene. The interaction of optical pulse…

Mesoscale and Nanoscale Physics · Physics 2014-01-23 Hamed Koochaki Kelardeh , Vadym Apalkov , Mark I. Stockman

For gapped graphene, we predict that an intense ultrashort (single-oscillation) circularly-polarized optical pulse can induce a large population of the conduction band and a large valley polarization. With an increase in the bandgap, the…

Mesoscale and Nanoscale Physics · Physics 2019-09-25 S. Azar Oliaei Motlagh , Fatemeh Nematollahi , Vadym Apalkov , Mark I. Stockman

We study theoretically interaction of a bilayer graphene with a circularly polarized ultrafast optical pulse of a single oscillation at an oblique incidence. The normal component of the pulse breaks the inversion symmetry of the system and…

Mesoscale and Nanoscale Physics · Physics 2021-11-10 Pardeep Kumar , Thakshila M. Herath , Vadym Apalkov

We theoretically show that buckled two-dimensional graphene-like materials (silicene and germanene) subjected to a femtosecond strong optical pulse can be controlled by the optical field component normal to their plane. In such strong…

Mesoscale and Nanoscale Physics · Physics 2015-10-02 Hamed Koochaki Kelardeh , Vadym Apalkov , Mark I. Stockman

The ability to manipulate electrons with the intense laser pulse enables an unprecedented control over the electronic motion on its intrinsic timescale. Present work explores the desired control of photocurrent generation in monolayer…

Mesoscale and Nanoscale Physics · Physics 2024-08-14 Navdeep Rana , Gopal Dixit

We study theoretically the strong-field absorption of an ultrafast optical pulse by a gapped graphene monolayer. At low field amplitudes, the absorbance in the pristine graphene is equal to the universal value of $2.3$ percent. Although the…

Mesoscale and Nanoscale Physics · Physics 2020-05-06 S. Azar Oliaei Motlagh , Ahmal Jawad Zafar , Aranyo Mitra , Vadym Apalkov , Mark I. Stockman

The Dirac-like quasiparticles in honeycomb graphene lattice are taken to possess a non-zero effective mass. The charge carriers involve to interact with a femtosecond strong laser pulse. Due to the scattering time of electrons in graphene…

Mesoscale and Nanoscale Physics · Physics 2017-01-31 Z. Ahmadi , H. Goudarzi , A. Jafari

We investigate coherent electron dynamics in graphene, interacting with the electric field waveform of two orthogonally polarized, few-cycle laser pulses. Recently, we demonstrated that linearly polarized driving pulses lead to…

Mesoscale and Nanoscale Physics · Physics 2018-11-20 Christian Heide , Takuya Higuchi , Heiko B. Weber , Peter Hommelhoff

In the model of gapped graphene, we have shown how the recently predicted topological resonances are solely related to the presence of an energy band gap at the $K$ and $K^\prime$ points of the Brillouin zone. In the field of a strong…

Mesoscale and Nanoscale Physics · Physics 2018-12-24 S. Azar Oliaei Motlagh , Vadym Apalkov , Mark I. Stockman

We study the non-equilibrium dynamics in a mesoscopic graphene ring excited by picoseconds shaped electromagnetic pulses. We predict an ultrafast buildup of charge polarization, currents and orbital magnetization. Applying the light pulses…

Mesoscale and Nanoscale Physics · Physics 2012-07-02 A. S. Moskalenko , J. Berakdar

We present analytical expressions for the current-current correlation function in graphene for arbitrary frequency, wave vector, doping, and band gap induced by a mass term. In the static limit we analyze the Landau (orbital) and Pauli…

Mesoscale and Nanoscale Physics · Physics 2011-06-16 Andreas Scholz , John Schliemann

Ultrafast optical pump-probe spectroscopy measurement on monolayer graphene observes significant optical nonlinearities. We show that strongly photoexcited graphene monolayers with 35 fs pulses quasi-instantaneously build up a broadband,…

Mesoscale and Nanoscale Physics · Physics 2015-06-15 Junhua Zhang , Joerg Schmalian , Tianqi Li , Jigang Wang

Spontaneous optical emission of graphene irradiated by intense single-cycle terahertz pulses was investigated experimentally and explained theoretically. We found that emitted photons are polarized predominantly perpendicular to the…

Mesoscale and Nanoscale Physics · Physics 2022-11-23 I. V. Oladyshkin , S. B. Bodrov , A. V. Korzhimanov , A. A. Murzanev , Yu. A. Sergeev , A. I. Korytin , M. D. Tokman , A. N. Stepanov

A model for energy spectrum of superlattice on the base of graphene placed on the striped dielectric substrate is proposed. A direct current component which appears in that structure perpendicularly to pulling electric field under the…

Mesoscale and Nanoscale Physics · Physics 2012-02-10 D. V. Zav'yalov , V. I. Konchenkov , S. V. Kryuchkov

High intensity laser pulses were recently shown to induce a population inverted transient state in graphene [T. Li et al. Phys. Rev. Lett. 108, 167401 (2012)]. Using a combination of hydrodynamic arguments and a kinetic theory we determine…

Mesoscale and Nanoscale Physics · Physics 2015-06-15 Junhua Zhang , Tianqi Li , Jigang Wang , Joerg Schmalian

We show that the optical excitation of graphene with polarized light leads to the pure valley current where carriers in the valleys counterflow. The current in each valley originates from asymmetry of optical transitions and electron…

Mesoscale and Nanoscale Physics · Physics 2015-05-28 L. E. Golub , S. A. Tarasenko , M. V. Entin , L. I. Magarill

We theoretically investigate the effect of broken inversion symmetry on the generation and control of ultrafast currents in a transparent dielectric (SiO2) by strong femto-second optical laser pulses. Ab-initio simulations based on…

We theoretically study the population inversion and negative dynamic conductivity in intrinsic graphene in the terahertz (THz) frequency range upon pulse photoexcitation with near-/mid-infrared wavelength. The threshold pulse energy…

Mesoscale and Nanoscale Physics · Physics 2015-06-11 A. Satou , V. Ryzhii , Y. Kurita , T. Otsuji

We theoretically investigate high-order harmonic generation (HHG) and its ellipticity in gapped graphene, driven by a femtosecond short-pulse laser at various orientation angles, employing the two-band density-matrix equations within the…

Atomic Physics · Physics 2025-05-21 Xinru Song , Xiaoyu Bu , Xiaohui Zhao , Rongxiang Zhang , Shang Wang , Fulong Dong
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